For an expanding primary school, a kit-of-parts timber system provided the perfect, sustainable new classroom building – one that could be quickly and easily assembled, and unproblematically dismantled at the end of its life.
Originally built in 1859, Old Newton Primary School sits in a rural setting just north of Stowmarket in the village of Old Newton, Suffolk. The school is made of a collection of buildings with a capacity for 105 pupils. Seeking to expand, the school secured funding to create a new self-contained classroom and library in an underused area overlooking the playground in 2023.
Pupils make good use of the new classroom’s integrated storage bench; © Matthew Walder
“My children go to the school, and we live pretty much next door to it,” explains Al Scott, Founder of IF_DO architects. “As a parent governor there, I was aware that the school was seeking to expand. An additional, standalone classroom had been decided upon, to free up space internally, and the location had been determined.”
The school had already approached a turnkey classroom delivery specialist, received a proposed design for a prefabricated volumetric solution and confirmed permitted development for it. There was a limited budget, and materials prices were rapidly rising at the time, but Al believed that IF_DO could design something better within those constraints.
Central to IF_DO’s vision for a better value building, was to incorporate flexible spaces such as the covered seating area overlooking the playground, and improved visual connectivity to the green spaces surrounding the classroom. Moreover, the new classroom would need to be delivered and built rapidly, with disruptive operations occurring only during school holidays.
So when in 2024 the school governors approached IF_DO Architects to propose an off-site manufactured solution to achieve this, it seemed a perfect fit for Natural Building Systems – with all the benefits of regenerative, natural materials, excellent indoor air quality, being free from VOCs and other contaminants – adding significant further value for the school on a limited budget.
A timber kit of parts was the ideal design solution for this standalone classroom; © Matthew Walder
Perfectly ADEPTed to the project
IF_DO developed a concept design which was simply optimized with support from Natural Building Systems to utilise its offsite-manufactured panel system, ADEPT. A kit-of-parts system, ADEPT’s wall panels and roof cassettes are made from timber and other biomaterials, and are designed for easy connection and installation.
“Working with Natural Building Systems was brilliant: we gave them our model and used their software to understand how we could tweak it a little to snap it as closely as possible to NBS’ cassettes,” Al relates. “It was seamless: NBS came back with a fully designed structurally integral insulated shell and core and the client – the schools – was very happy with it.”
IF_DO had been working with Natural Building Systems on a few other projects – among them David Nicholson’s own home. They were interested in the ADEPT system and were keen to use it in a project of their own, as proof of concept for the practice: evidence that a kit-of-parts, pre-manufactured system designed for circularity, using entirely natural materials, could work efficiently.
David had first contacted them having been impressed by IF_DO’s work on The Hithe, a demountable commercial building for local startups in London’s Borough area – designed, of necessity, to be disassembled after a lease of ten years. In many ways, the Adept system is a ready-made solution to the challenges IF_DO had to solve from scratch when designing The Hithe.
“For The Hithe, we put a lot of R&D into investigating how we could tweak six panels to make them structurally robust but easy enough to take apart and put back together without breaking,” Al recalls. “If we had been aware of David’s system at the time, it would have been perfect. It has great sustainability benefits and internal air quality, making it very well suited to a classroom environment.”
The new building sits neatly in the playground area; © Matthew Walder
Design and delivery
“We managed to deliver a very slightly bigger net internal area than the previous design,” Al tells us. “It’s a simple structure with some nice features, such as the large picture window overlooking a horse chestnut tree, and the integrated storage bench which links it to the playground site. We incorporated some additional social and practical benefits to the building.”
Following early consideration of a suspended deck, a conventional groundbearing slab was specified to address ground conditions. The project was tendered and let in January 2024 under a Design and Build contract to local builders, Mixbrow Construction, with NBS nominated to design and supply the superstructure elements. Ground works commenced in September 2024 with the NBS components delivered in October; Mixbrow completed the project in December 2024.
The exterior
The building is clad with a vented timber rainscreen of ThermoWood. The cladding comes down to a masonry upstand to the damp proof course above the slab. The board is cut to follow the line of the playground, which slightly slopes, with a gap maintained of about 50mm. The exterior of the roof is a simple sheet of PVC-coated corrugated metal.
“The school was a very supportive client,” Al reflects. “It probably helped that another fairly recent extension to the school was in part clad in timber, and has lasted well. We did talk to them about maintenance and potential treatment options for the timber, but the Thermowood has excellent credentials in itself.”
For the internal finish, a wood wool board was used; © Matthew Walder
Circuland and digital materials passports
Natural Building Systems received some grant funding allowing them to partner with Circuland, a specialist in supplying and maintaining digital passports for materials. They have embedded each component of the ADEPT system with a digital materials passport; Circuland’s online platform records all that information.
“They have a very user-friendly, visual-based platform and categorise all the components in terms of their circularity,” David tells us. “It allows a customer to access every detail of every product material that has gone into the building – which can inform maintenance and later reuse. So it’s particularly valuable for ADEPT, as each component is reusable and can be separately demounted.”
Sustainable materials and their advantages
“Air quality is a particular focus,” David states. “How can we improve indoor air quality using a breathable thermal envelope with entirely natural materials? Testing with BRE found background VOCs of 1/10th of the BREAAM standard. And testing for CO2 is even more interesting. High indoor CO2 levels reduce cognitive function and increase fatigue but also trigger mechanical ventilation systems. If you can reduce CO2 in a classroom then you can reduce energy costs, as well as helping children concentrate!”
© Matthew Walder
“Testing with academic partners suggests that our hemp composite insulation effectively ‘buffers’ CO2 in the air during use – reducing peaks during periods of high occupancy. This is something we’re exploring further with monitoring currently underway at Old Newton School.”
For the internal finish, a wood wool board was used, which helps to preserve a breathable envelope, and has good acoustic properties; a painted plywood wainscoting provides the finish at the bottom. The roof uses large-format cassettes made from an I-joist system, with hemp wool insulation.
“The design was ultimately an elegantly economical solution to meet a simple brief: a single room with no particularly complex services,” Al reflects.
All in all, it’s a project that abundantly demonstrates how easily this timber modular system can supply a cost-effective improvement to the standard form of construction.
Read our case study on The Hithe, a demountable project also designed by IF_DO architects
